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  <p class="align-right"><strong>built-in predicate</strong></p>
<section id="logtalk-load-1">
<span id="predicates-logtalk-load-1"></span><span id="index-0"></span><h1><code class="docutils literal notranslate"><span class="pre">logtalk_load/1</span></code><a class="headerlink" href="#logtalk-load-1" title="Link to this heading"></a></h1>
<section id="description">
<h2>Description<a class="headerlink" href="#description" title="Link to this heading"></a></h2>
<div class="highlight-logtalk notranslate"><div class="highlight"><pre><span></span><span class="k">logtalk_load</span>(<span class="nv">File</span>)
<span class="k">logtalk_load</span>(<span class="nv">Files</span>)
</pre></div>
</div>
<p>Compiles to disk and then loads to memory a <a class="reference internal" href="../../glossary.html#term-source-file"><span class="xref std std-term">source file</span></a> or a list
of source files using the default compiler flag values. The Logtalk source
file name extension (by default, <code class="docutils literal notranslate"><span class="pre">.lgt</span></code>) can be omitted. Source file
paths can be absolute, relative to the current directory, or use
<a class="reference internal" href="../../glossary.html#term-library-notation"><span class="xref std std-term">library notation</span></a>. This predicate can also be used to compile Prolog
source files as Logtalk source code. When no recognized Logtalk or Prolog
extension is specified, the compiler tries first to append a Logtalk source
file extension and then a Prolog source file extension. If that fails, the
compiler tries to use the file name as-is. The recognized Logtalk and Prolog
file extensions are defined in the <a class="reference internal" href="../../glossary.html#term-adapter-file"><span class="xref std std-term">backend adapter files</span></a>.</p>
<p>When this predicate is called from the top-level interpreter, relative source
file paths are resolved using the current working directory. When the calls
are made from a source file, relative source file paths are resolved
using the source file directory.</p>
<p>Note that only the errors related to problems in the predicate argument
are listed below. This predicate fails on the first error found during
compilation of a source file. In this case, the source file contents is
not loaded.</p>
<p>Depending on the <a class="reference internal" href="../../glossary.html#term-backend-Prolog-compiler"><span class="xref std std-term">backend Prolog compiler</span></a>, the shortcuts <code class="docutils literal notranslate"><span class="pre">{File}</span></code>
or <code class="docutils literal notranslate"><span class="pre">{File1,</span> <span class="pre">File2,</span> <span class="pre">...}</span></code> may be used as an alternative. Check the adapter
files for the availability of these shortcuts as they are not part of
the language (and thus should only be used at the top-level
interpreter).</p>
</section>
<section id="modes-and-number-of-proofs">
<h2>Modes and number of proofs<a class="headerlink" href="#modes-and-number-of-proofs" title="Link to this heading"></a></h2>
<div class="highlight-logtalk notranslate"><div class="highlight"><pre><span></span><span class="k">logtalk_load</span>(<span class="o">@</span>source_file_name) <span class="o">-</span> zero_or_one
<span class="k">logtalk_load</span>(<span class="o">@</span>list(source_file_name)) <span class="o">-</span> zero_or_one
</pre></div>
</div>
</section>
<section id="errors">
<h2>Errors<a class="headerlink" href="#errors" title="Link to this heading"></a></h2>
<div class="line-block">
<div class="line"><code class="docutils literal notranslate"><span class="pre">File</span></code> is a variable:</div>
<div class="line-block">
<div class="line"><code class="docutils literal notranslate"><span class="pre">instantiation_error</span></code></div>
</div>
<div class="line"><code class="docutils literal notranslate"><span class="pre">Files</span></code> is a variable or a list with an element which is a variable:</div>
<div class="line-block">
<div class="line"><code class="docutils literal notranslate"><span class="pre">instantiation_error</span></code></div>
</div>
<div class="line"><code class="docutils literal notranslate"><span class="pre">File</span></code>, or an element <code class="docutils literal notranslate"><span class="pre">File</span></code> of the <code class="docutils literal notranslate"><span class="pre">Files</span></code> list, is neither a variable nor a source file name:</div>
<div class="line-block">
<div class="line"><code class="docutils literal notranslate"><span class="pre">type_error(source_file_name,</span> <span class="pre">File)</span></code></div>
</div>
<div class="line"><code class="docutils literal notranslate"><span class="pre">File</span></code>, or an element <code class="docutils literal notranslate"><span class="pre">File</span></code> of the <code class="docutils literal notranslate"><span class="pre">Files</span></code> list, uses library notation but the library does not exist:</div>
<div class="line-block">
<div class="line"><code class="docutils literal notranslate"><span class="pre">existence_error(library,</span> <span class="pre">Library)</span></code></div>
</div>
<div class="line"><code class="docutils literal notranslate"><span class="pre">File</span></code> or an element <code class="docutils literal notranslate"><span class="pre">File</span></code> of the <code class="docutils literal notranslate"><span class="pre">Files</span></code> list, does not exist:</div>
<div class="line-block">
<div class="line"><code class="docutils literal notranslate"><span class="pre">existence_error(file,</span> <span class="pre">File)</span></code></div>
</div>
</div>
</section>
<section id="examples">
<h2>Examples<a class="headerlink" href="#examples" title="Link to this heading"></a></h2>
<div class="highlight-logtalk notranslate"><div class="highlight"><pre><span></span><span class="c">% compile and load the &quot;set&quot; source file in the</span>
<span class="c">% current directory:</span>
| <span class="o">?-</span> <span class="k">logtalk_load</span>(set).

<span class="c">% compile and load the &quot;tree&quot; source file in the</span>
<span class="c">% &quot;types&quot; library directory:</span>
| <span class="o">?-</span> <span class="k">logtalk_load</span>(types(tree)).

<span class="c">% compile and load the &quot;listp&quot; and &quot;list&quot; source</span>
<span class="c">% files in the current directory:</span>
| <span class="o">?-</span> <span class="k">logtalk_load</span>([listp, list]).
</pre></div>
</div>
<div class="admonition seealso">
<p class="admonition-title">See also</p>
<p><a class="reference internal" href="logtalk_compile_1.html#predicates-logtalk-compile-1"><span class="std std-ref">logtalk_compile/1</span></a>,
<a class="reference internal" href="logtalk_compile_2.html#predicates-logtalk-compile-2"><span class="std std-ref">logtalk_compile/2</span></a>,
<a class="reference internal" href="logtalk_load_2.html#predicates-logtalk-load-2"><span class="std std-ref">logtalk_load/2</span></a>,
<a class="reference internal" href="logtalk_make_0.html#predicates-logtalk-make-0"><span class="std std-ref">logtalk_make/0</span></a>,
<a class="reference internal" href="logtalk_make_1.html#predicates-logtalk-make-1"><span class="std std-ref">logtalk_make/1</span></a>,
<a class="reference internal" href="logtalk_library_path_2.html#predicates-logtalk-library-path-2"><span class="std std-ref">logtalk_library_path/2</span></a></p>
</div>
</section>
</section>


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